Latticework beam for reinforcing cast walls or ceilings

ABSTRACT

A reinforcement for a cast material for the fabrication of walls and ceilings of a structure which has two latticework beams interconnected by spaces using plastic plugs extending through aligned bores of the spacers and the longitudinal chords of the beams. The beams themselves have the longitudinal chords connected together by zig-zag strips and the longitudinal chords, zig-zag strips and spacers are all formed from galvanized sheet steel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage of PCT/1895/00028 filed Feb. 9,1995 and based, in turn, on Austrian National Application A 268/94 filedFeb. 10, 1994 under the International convention.

FIELD OF THE INVENTION

The invention relates to a latticework beam for reinforcing walls orceilings made of cast material, consisting of two longitudinal chordswith diagonal bars between them, whereby the diagonal bars consist of asheet steel strip bent in a zig-zag shape, running through thelatticework beam and which is connected at its bending points with theprofiled longitudinal chords, also made of sheet steel strips.

BACKGROUND OF THE INVENTION

In a latticework beam known from German Patent 835 647, the continuoussheet steel strip of the diagonal bars runs so that the width of thestrip is parallel to the plane of the latticework beam. It seems thatthe inventor considered this to be necessary, in order to achieve aconnection between the longitudinal chords and the diagonal bars solelyby clamping. Here the disadvantage is the lack of rigidity of thelatticework beam in transverse direction, which is particularlynoticeable during transport.

OBJECT OF THE INVENTION

It is the object of the invention to provide a latticework beam of theaforementioned kind, whose production is simple, but which still has ahigh degree of rigidity. Moreover with such latticework beams it shouldbe possible to form a support framework in a simple manner.

SUMMARY OF THE INVENTION

This object is achieved in a steel latticework beam wherein that thewidth of the trough-shaped sheet steel strip forming the diagonal barsand the width of the longitudinal chords extend transversely to thelongitudinal median plane of the latticework beam. In the area ofjunction points, the sheet steel strip of the diagonal bars has asegment running parallel to the longitudinal chords.

The sheet steel strip can be obtained by cutting galvanized steel sheetsinto strips and forming them accordingly. Since the zinc has thetendency to move to the cut edges, these cut edges are also protectedagainst corrosion.

For the connection of the diagonal bars with the longitudinal chords, ithas proven to be suitable to connect the throughgoing sheet steel stripof the diagonal bars with the longitudinal chords at junction points bycompression.

A support framework of latticework beams according to the invention canalso be formed in a simple way by providing the longitudinal chords withspaced-apart bores and by connecting at least two approximately parallellatticework beams with spacers also provided with bores, by means ofconnection elements placed in the bores, whereby the spacers consist ofa galvanized sheet steel strip.

In order to simplify the production and storage, the sheet steel stripsof the longitudinal chords and the spacers are of the same type.

The connection between the longitudinal chords and the spacers does nothave to withstand great forces, it serves merely for securing thelatticework beam placed in a mold, whereby subsequently a cast mass,particularly concrete or lightweight concrete, is poured into the mold.It is therefore possible that the connection elements be designed asplastic plugs equipped with an elastic tab having a projection, whichresiliently engages and disengages when inserted into a bore. Suchplastic plugs have only to be pressed into the bores to insure a firmconnection between the longitudinal chords and the spacers.

The plastic plugs may also be used in a simple way to insure the secureembedding of the support framework in the cast mass. This simple stepconsists in that the plastic plugs project beyond the spacers on theside opposite to the tabs. Therefore due to the plastic plugs a space isforcibly maintained between the mold walls and the support framework.

BRIEF DESCRIPTION OF THE DRAWING

The above and other objects, features, and advantages will become morereadily apparent from the following description, reference being made tothe accompanying drawing in which:

FIG. 1 is a cross sectional view of a support framework of latticeworkbeams according to the invention;

FIG. 2 is a side view of a latticework beam; and

FIG. 3 shows on an enlarged scale a section through the junction pointbetween a longitudinal chord and a spacer.

SPECIFIC DESCRIPTION

According to the drawing a latticework beam consists of two longitudinalchords 1 and 2 and diagonal bars 3 running between them. Thelongitudinal chords 1 and 2, as well as the diagonal bars 3, eachconsist of a galvanized sheet steel strip, which has a trough shape. Thediagonal bars 3 are thereby slightly narrower than the longitudinalchords 1 and 2 and are formed by a continuous sheet steel strip, whichis connected by compression with the longitudinal chords at the junctionpoints 4. The dents formed during compression are marked with thenumeral 5 in FIG. 2.

As can be seen from FIG. 1, in the area of the junction points 4, thesheet steel strip of the diagonal bars 3 has segments running parallelto the longitudinal chords 1 and 2, at each the sheet steel strip andthe longitudinal chords 1, 2 are pressed together.

According to FIG. 1 the longitudinal chords 1 of two mutually parallelrunning latticework beams are connected to each other by spacers 6.These spacers are made the same way as the longitudinal chords 1, e.g.they consist of a galvanized sheet steel strip and have the same shapeand size as the longitudinal chords 1.

The connection between the longitudinal chords 1 with the spacers 6shown in FIG. 3 is made by means of plastic plugs 7, which haveresilient tabs 8. In the area of the resilient tabs 8 a projection orstep 9 is provided and opposite to the tabs 8 extends a cylindrical part10, which ends in a peripheral projection or step 11. The plastic plug 7is slotted in the area of the tab 8.

The longitudinal chord 1, as well as the spacer 6, is provided withbores 12 traversed by the plastic plugs 7. When the plastic plug 7 isplugged into the bores 12, the tabs 8 are pressed against each other, sothat the plastic plug 7 can be pushed through. After reaching the finalposition shown in FIG. 3, the tabs 8 spring back, so that the projectionor step 9 lies against the longitudinal chord 1. The projection or step11 lies against the spacer 6, so that a secure connection of thelongitudinal chord 1 and the spacer 6 results.

Within the framework of the invention it is possible to make manychanges. So for instance a kind of snap-button connection can also beused for the connection between the spacers 6 and the longitudinalchords 1, 2. The sheet steel strip can also have further, even differentshapes, respectively canted profiles to increase stability.

I claim:
 1. A reinforcement for a cast material for a structure,comprising:two mutually parallel transversely spaced latticework beams,each of said beams including:two longitudinal chords of galvanizedchamfer-shaped channels of sheet steel strip, and diagonal bars betweensaid longitudinal chords and formed by a galvanized chamfer-shapedchannel of sheet steel strip in a zig-zag pattern connected atrespective bends with said longitudinal chords, said longitudinal chordsbeing formed with spaced apart bores therein; transverse galvanizedsheet steel spaces bridging the longitudinal chords of said beams andhaving bores aligned with the bores of the longitudinal chords bridgedby the respective spacers; and plastic plugs connecting said spacers tothe longitudinal chords of said beams, said plastic plugs having elastictabs traversing aligned bores, and respective steps on said tabs forengagement and disengagement with said longitudinal chords.
 2. Thereinforcement defined in claim 1 wherein said plastic plugs projectbeyond said spacers at sides of said plugs opposite the tabs thereof. 3.The reinforcement defined in claim 2 wherein said bends are connected tosaid longitudinal chords by a pressed junction therebetween.
 4. Thereinforcement defined in claim 1 wherein said bends are connected tosaid longitudinal chords by a pressed junction therebetween.